Last item in TextBoxList can not be removed (tags) and beautify disabled mode

How to reproduce

• Create an EP page
• In the page edit form, add multiple categories
• Save page
• Open page meta edit form again
• Delete all categories
• Save
• Open page meta edit form again
• => NOK: all categories but the last one is deleted

It is not possible to delete the last category. 

Disabled layout 

When the component is disable, a simple coma separated list was showed. It should be rendered like the input form as tags.